The invention relates to a means for removing poles, specifically, an extractor that utilizes a cylinder and ram assembly that attaches to a pole and extracts it from the substrate, without damaging the surroundings.
Current methods to remove utility poles, posts or the like (herein referred to collectively as poles) from the ground rely upon a mobile derrick. In order to remove a pole, the derrick is connected to a pole at or near the top of the pole. The pole is then loosened by moving the boom of the derrick forwards, backwards and sideways. If the pole can be loosened in this manner, the derrick is then used to lift the pole from the hole. This approach to removing poles unduly stresses the boom, the turning means and the hydraulic system of the derrick, resulting in costly repairs, re-certification of the equipment and loss of machine hours.
Frequently, the pole cannot be loosened with the derrick. Alternative methods for loosening are then employed. One approach is to simply employ workers to dig a hole around the pole. Another method involves the use of vacuum. A large capacity vacuum, such as that used to clean out storm sewer manholes, removes substrate from around the pole. The pole is then lifted with the aid of the derrick. The disadvantages of these approaches include manpower costs, disturbance of the surrounding substrate and, in the case of the vacuum approach, additional equipment costs.
Approaches that have been developed to overcome the above-mentioned deficiencies include the use of a single hydraulic jack as taught in U.S. Pat. Nos. 3,173,658 and 3,163,398. The single hydraulic jack has the following disadvantages:
1. The jack has to be assembled to extract the pole and then disassembled in order to move it to another pole. This is time consuming and can be hazardous to the workers;
2. There is frequently insufficient power to extract the pole;
3. The base is too small and hence it frequently is driven into the ground rather than the pole being extracted;
4. The shape of the base restricts the size and shape of poles that can be removed.
The apparatus described in U.S. Pat. No. 4,822,006, while overcoming a number of deficiencies of the prior art, also has disadvantages. These impact on the speed, effectiveness, and utility of the invention as follows.
In U.S. Pat. No. 4,820,006 there are two hydraulic jacks that must work in concert. In order for the jacks to work in concert, the hydraulic lines must provide the same pressure. Unfortunately, hydraulic lines are notorious for bleeding. If this occurs on one line and not the other, operation of the two jacks will become uncoordinated.
Another disadvantage of the invention described in U.S. Pat. No. 4,822,006 is that the base is free standing. This means that the base could be driven into the ground when the pole is being extracted, thereby reducing the effectiveness of the apparatus. It also means that the apparatus must be loaded and unloaded from a suitable piece of heavy equipment prior to and after use. Again, this takes time and can be hazardous to the workers.
In U.S. Pat. No. 4,822,066 the applicant notes that rotation of the head is essential for the operation of the apparatus. This precludes the removal of concrete poles, as in order to lift these, a cable or chain must be threaded through an opening in the pole.
A final disadvantage of the prior art is that the U or V shape of the base places a restriction on the diameter and shape of the pole that can be extracted. The base must fit around the pole, such that one hydraulic jack is on one side of the pole and the other hydraulic jack is on the other side of the pole.
It is the objective of the present invention to overcome the deficiencies in the prior art.
According to the invention, a pole extractor is provided to rapidly and safely remove poles. The pole extractor has a base and a hydraulically operable cylinder and ram assembly. The base functions to support the cylinder and ram assembly and to displace the force exerted during extraction of a pole. In order to do so, the base is coupled to an attachment means to define a slot. This slot accepts and holds a mobile positioning device, which for example, may be a piece of heavy equipment or an attachment on the heavy equipment. A variety of heavy equipment attachments can be used, for example a bucket or blade, hereinafter referred to collectively as a bucket.
The cylinder and ram assembly is pivotally mounted on the base to facilitate working on uneven or inclined surfaces. During operation, a holding means, which is attached to a connecting means on a ram, releasably holds the pole. Extension and retraction of the ram is controlled by an actuating means which is preferentially remote from the pole extractor, but which is in fluid communication with the cylinder and ram assembly by means of a fluid inlet and a fluid outlet. The ram is actuated in order to extract the pole from a substrate.
From the above description it is clear that the invention provides a rapid, safe means for extracting poles from the ground or any other substrate.